1. Field of the Invention
The present invention employs associative complexes of water soluble and/or water dispersible polymers and polymeric fluorosurfactants, compositions and methods thereof, for modifying substrates to provide treated articles with surface protective properties including easier cleaning, easier next time cleaning, increased water and/or oil repellency, increased stain and/or soil repellency, and increased resistance to bio-fouling and environmental contamination.
2. Background of the Invention
Consumers are dissatisfied with their ability to prevent water and soils, such as water spots, soap scum, toothpaste, scale, greasy soils, brake dust, grime, rust, and toilet ring, from soiling and building up on household surfaces and other exposed materials. It would be desirable to have treatment means that would easily modify or enhance the surface protective properties of a wide variety of materials to retain and/or maintain their “like new” appearance and/or clean state for longer periods of time, particularly when exposed to water, soil and the like. It would further be desirable to have a treatment means compatible with cleaning aids, so that cleaning and treatment of soiled surfaces could be done either in conjunction or simultaneously with the treatment means providing enhanced protection.
Consumers also desire cleaners and treatments that are convenient to use, provide “easier cleaning” or reduce cleaning effort, for example the need for less surface scrubbing or buffing, during the initial cleaning and/or treatment step. Even more desirable would be to have a treatment means whereby treated surfaces would exhibit an improved “next time” cleaning benefit; whereby the surface is modified to be either self-cleaning and/or more easily cleaned in a subsequent cleaning and/or treatment step. Also desirable would be a treatment means that would renew the surface protective properties of treated surfaces and articles, so that the maintenance of the surface protective properties is achieved in circumstances where an optional cleaning step or cleaning agent is not employed, or where access to the surfaces requiring cleaning and/or protection is restricted.
It has now been discovered that associative complexes of water soluble and/or water dispersible polymers and selected polymeric fluorosurfactants, either formed in situ or formulated into treatment compositions, optionally combined with cleaning agents and other adjuncts, may be employed using a variety of application and treatment methods, to modify surfaces of materials to provide treated articles exhibiting the enhanced surface protective properties described above.
Surface protecting compositions and treatment methods are well known in the art, and are employed to reduce or prevent water, oil, soils and microorganisms from adhering to the treated surfaces.
One approach is to coat surfaces with a macroscopically thick and relatively permanent stain-proofing treatment that essentially acts as a paint-like coating to seal and cover the surface. A reactive material that either chemical bonds to the surface or that internally cross links is generally employed in this approach to form a cured film. With this type of treatment, the surface generally must be cleaned and/or washed prior to application to ensure good adhesion of the film to prevent delamination or inclusion of air pockets that would lead to film degradation. The visual appearance of the treated surfaces are also significantly altered with this approach.
In another approach, a sacrificial coating may be applied to protect a surface, which upon normal attrition and wear due to environmental exposure or microbial challenge, and/or upon a subsequent cleaning operation, is substantially removed from the surface taking any adhered dirt, soils and the like with it, thereby exposing the underlying original surface. In this approach, separate protective treatment and cleaning steps must be employed, and the degree of protection generally obtained is dependent on the thickness of the sacrificial coating applied, and thus thicker films are generally preferred. This approach is less suitable for submerged surfaces or those that are frequently exposed to aqueous fluids or water.
Yet another approach particularly suited for treating surfaces in closed systems that are either intermittently or continuously exposed to a fluid system, such as in water handling and distribution systems including for example water cooling towers, toilets, bioreactors, and the like, is to add some surface active agent to the fluid system so that exposed or submerged surfaces are continuously replenished with the agent to achieve some protective properties. Generally, very high levels of such agents must be employed with this approach to ensure that an effective level is absorbed onto the target surface areas. Employing less water soluble materials with higher surface affinity, that is those exhibiting a greater tendency to absorb onto the surface, may be employed to overcome the need for high levels of the material present in the fluid system, but this limits the choice of materials and may further present problems including undesirable build-up on the surfaces and/or precipitation from solution.
An alternative approach is to deposit a protective polymer on a surface that can act to reduce the adhesion of dirt, soils and microbes. Generally, the polymers employed must have lower water solubility in order to favorably deposit onto the target surface, and/or have chemistries specifically selected with respect to the targeted surface to insure effective absorption affinity. When using less water soluble materials, which is typically preferred for system that are more effective at treating an non-selective surface, the art has employed various means to disperse or suspend these polymers in aqueous systems to make practical treatment compositions. The use of dispersion aids, such as solubilizers and emulsifiers, however, is known to reduce the effectiveness of polymeric materials from depositing onto the target surface owing to their stabilization in the solution. Thus, higher concentrations or process steps that require drying to deposit an effective level of the material may be required. Further, the presence of residual dispersion aids in the deposited polymer films may alter or lower the surface protection benefit or require a subsequent rinsing step to achieve the desired properties.
Thus, the art is in search of treatment compositions that provide stable, but thin and invisible films on treated surfaces with enhanced surface protective properties, such as water repellency and reduced adhesion of soil, biological and environmental contaminants. The art is also in need of treatment compositions that can also be employed to simultaneously clean and treat the surfaces so that separate cleaning and treatment steps are not required. In addition, with growing environmental concerns linked with the use of compounds, such as for example perfluorinated surfactants and polymers with long perfluoroalkyl chains that have preferred surface modifying agents yet possess some undesirable toxicological properties including the tendency to bio-accumulate, there is a need for materials that offer similar protective properties but which employ alternative materials that are easy to use, are effective at lower levels and which have less environmental impact.